Abstract: A reflection-type photosensor is formed in a body of U-shape with lenses formed on arms of the U. The optical axes of the lenses intersect at a location outside of the U-shape at a position above the gap between the arms. The surface roughness of facing surfaces of the arms is such as to cause light dispersion. Leads are formed in parallel within the body and exit the bottom surface. The light emitter and light detector may be mounted on thinned parts of first leads such that peripheral portions of the first leads serve as reflective surfaces.